To measure the pungency of chili peppers, scientists have devised the Scoville scale. The scale measures the amount of capsaicinoids present in the pepper, the main component responsible for its burning sensation. The higher the number of Scoville heat units, the hotter the pepper is. Fortunately, there is an accurate and widely used version of the scale.
The Scoville Scale is a heat chart, displaying how hot chili peppers are in terms of their capsaicin content. The highest-scoring chili peppers contain pure capsaicin, which is the active ingredient that gives chili peppers their distinct spiciness. By comparison, green bell peppers contain no heat at all. The Scoville scale is based on the results of tests involving taste testers who extract the heat from dehydrated chiles. They then dilute the sample with sugar water and measure the resulting heat.
On the Scoville scale, the hottest pepper is the Carolina Reaper Pepper. With 2,200,000 Scoville heat units, it will send your taste buds to hell. Other hottest peppers include the Trinidad Scorpion and Ghost Pepper.